The Great Barrier Reef Foundation has revealed it has spent $800,000 on "project management" since receiving a $440 million grant in June, and expects to spend more than $7 million on administration this financial year.

"That's operational and project management costs, it's a range of things. I would be happy to take that question on notice and give you more a fulsome [response] but yes, $800,000 to date."

Ms Marsden said she was confident the foundation could raise "hundreds of millions" for the reef using its co-investment strategy and confirmed the Government did not set a benchmark for fundraising when the grant was offered.

She also confirmed the foundation would accept funding from fossil fuel companies.

"Our view is there is a role for every Australian business to play a role in reef protection activities," she said.

"We have a range of iconic Australia businesses that support us from a range of industries and some of these are resource companies.

"These organisations have a first-hand experience on the impacts of climate change and other pressures on the reef."

'I flew here in a plane'

Greens senator Sarah Hanson-Young argued the foundation did not seem to acknowledge the impact fossil fuel companies were having on climate change and the reef.

"You don't see a contradiction between half a billion dollars of public money going to an organisation that has been created to deal with the problem created by climate change, taking money from fossil fuel companies?" Senator Hanson-Young asked.

Foundation chairman John Schubert replied: "We are all the cause of climate change, it is not just fossil fuel companies," he said.

"Fossil fuel companies are basically reacting to the demand of us. I flew here in a plane."

He also elaborated on the April meeting with Mr Turnbull and then environment minister Josh Frydenberg, at which the decision to donate the money was discussed.

Mr Schubert said he had no idea about the grant offer prior and he was not told in advance what the meeting was about.

He said Mr Turnbull took charge of the meeting and there was no agenda nor minutes taken by the two staffers present.

"You asked 'was I surprised?' … but my overwhelming initial reaction was, 'This is fabulous news for the Great Barrier Reef, this is what is needed'," Dr Schubert said.

Foundation 'focused on practical outcomes'

Dr Schubert said he had not spoken to Mr Turnbull since the April meeting and that he believed the foundation was chosen for the grant because of its "track record" and its focus on "practical outcomes".

The foundation also confirmed its scientific committee had met only once since the grant was awarded, and that funding priorities were not discussed in detail.

Ms Marsden said the foundation had only provided two years' worth of financial records to the Government in May, a month after the grant was offered.

She said she was unaware the Government's solicitor had been conducting due diligence on the foundation prior to the grant offer, and that no documentation was requested from the foundation until after the offer.

The inquiry also questioned former Origin Energy managing director Grant King about his motivations for becoming a director of the foundation.

Mr King, who is also the Business Council of Australia president, said he took on a directorship at the foundation in a personal capacity because of his passion for the Barrier Reef.

The inquiry asked if the organisation should be pushing for higher emissions reduction targets than the Paris agreement.

"Australia's commitment is clearly the 26 to 28 per cent — which was the Paris commitment, and in whatever capacity I'm in I fully support that commitment," Mr King said.

"I believe it's essential Australia meets that commitment, and my view is that we've got to get there before we can get to any higher number.

"But if you mean 45 per cent reduction on 2005 levels by 2030, which is obviously significantly higher than the Paris commitment — then at the end of the day I see very little analysis here in Australia of the effect of that on the economy."

Mr Schubert said it was not the foundation's role to be advocating on climate change policy.

"The field of advocacy on the environmental issues and climate change specially is very crowded. There is a huge number of organisations and people involved in that, trying to get more momentum," he said.